Old South Bend lathe...

Yeah, you really, really gotta take to heart, that essay on Klunkers!

A couple thou taper over several inches, amounts to almost nothing over the usual length of the parts most guys will be making. Esp in parts that are still really good, if built to a plus or minus 3 or 5 thou tolerance.

It really is a place where doing the actual math on it to see what numbers are there, is well worth the time. Trig! Yay! Wear on the ways has an effect, but the end result of that wear only needs to be an issue if you cannot learn how to work with it, and around it.

The amount of metal that you can remove by pressing your thumb against the back of the tool post, can be quite a bit more! Esp. with a dead sharp cutting tool.

You can literally, learn how hard you need to press against the lathe to make the lathe cut straight. It is part of the dirty tricks that you need to learn a bit about, and play with, when you are playing with those old, worn machines.
If you were trying to make a living with it, you really should have bought a newer machine. But you got it for not much money, so what you really need to do is get more than your money worth out of it. Maybe a LOT more.

Get yourself some -T6 or harder aluminum rod to play with. If you have old barrels, they are either Chrome-Moly (4140, and similar designations) or in the stainless ones, often 416 steel. All very free machining stuff. Stay clear of cheap 1018 unless you can live with lousy surface finishes. Not that good finishes cannot be got, but they are misery to get, compared to the free machining stuff.

Cheers
Trev
 
trevj said:
Yeah, you really, really gotta take to heart, that essay on Klunkers!

A couple thou taper over several inches, amounts to almost nothing over the usual length of the parts most guys will be making. Esp in parts that are still really good, if built to a plus or minus 3 or 5 thou tolerance.

It really is a place where doing the actual math on it to see what numbers are there, is well worth the time. Trig! Yay! Wear on the ways has an effect, but the end result of that wear only needs to be an issue if you cannot learn how to work with it, and around it.

The amount of metal that you can remove by pressing your thumb against the back of the tool post, can be quite a bit more! Esp. with a dead sharp cutting tool.

You can literally, learn how hard you need to press against the lathe to make the lathe cut straight. It is part of the dirty tricks that you need to learn a bit about, and play with, when you are playing with those old, worn machines.
If you were trying to make a living with it, you really should have bought a newer machine. But you got it for not much money, so what you really need to do is get more than your money worth out of it. Maybe a LOT more.

Get yourself some -T6 or harder aluminum rod to play with. If you have old barrels, they are either Chrome-Moly (4140, and similar designations) or in the stainless ones, often 416 steel. All very free machining stuff. Stay clear of cheap 1018 unless you can live with lousy surface finishes. Not that good finishes cannot be got, but they are misery to get, compared to the free machining stuff.

Cheers
Trev
Click to expand...

Nicely said Trev, just think I'm only a finger or thumb away for glory .
Cheers
Brian
 
I have another bit to add to what these guys have already said. Run that old machine a pile and learn what works for you. It will make you think outside the box a lot and it's great mental exercise. Learning how to work with what you have to get the end result you want is really the fun of it.

I had a 9" SB briefely, then I sold it and bought a 12x36 Clausing that is a little older but basically brand new. The Clausing uses roller bearings in the headstock vs plain bearings in the SB. The SB would cut harder material to a glass smooth finish. The Clausing will not. The Clausing has a bunch of other features I like more than the SB, but I also got lucky and mine came with spare parts which is a good thing because not many of them this vintage are out there.

The SB uses a more normal height compound too. My 12" lathe uses the same post as a mini lathe. This sucks because I'm limited to small tooling. I modified a Sieg quick change post and gained a lot of rigidity that way though and am satisfied with it now. The Clausing can run much higher spindle speeds for a short time though, which is nice for turning wood.

For tooling, I've done lots with both hss and carbide. Buy good carbide and keep it sharp. HSSis handy but limited. If you learn to use carbide and figure out the right insets for your application even the negative rake holders will cut like butter. You aren't going to be running large radious inserts on a small lathe. Not enough power or rigidity. I use kennemetal inserts and holders I bought used on eBay. 10 holders set me up, and a few of each insert has made it well over a year of steady hobby use. You are going to break inserts while you are learning, just a warning. Learning hss you will be burning up tools steady and work hardening your pieces into constant frustration. I've found using both for specific applications is best and the least frustrating. Especially with no power and a relatively fast feed like the Clausing has. Basically what I'm saying is learn what works for you and how to apply it to what you are doing. None of this stuff is written in stone and with some thinking anything can be done.

Another trick I learned with the SB, for the flat belt I used a serpentine belt cut and sewn together with high test fishing line. Run it flat side in to your pulleys. They are super tacky and with even a pretty loose belt you will get the most out of your lathe's limited power.
 
A quick change tool post is really worth having. The cheapest I've seen that look half decent are on eBay. I do like the old rocker posts though because it's so easy to set the tool height and angle. The four sided holders without height adjustment are nothing but a PITA IMO, unless you're using factory carbides with cutting edges at exactly the same height.
 
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That picture helps a lot.

With the upper pulley on the jack shaft being that big and with the belt on the smaller pulley you are already in the slower speed range.

The upper V belt pulley is SUPPOSED to be a two stepper as well. So at some point this was changed for some reason. The stub portion of the shaft sticking out suggests to me that this is the case. If you get a new one to replace the one shown I'd look for the larger size to be roughly what you have and the next one down to be only a touch smaller since it will mate up with the larger motor V and produce the upper speed range. The step up of the lower pulley will be a lot of gain already. Which is why I'm suggesting that the upper step pulley sizes be pretty close.

Don't discount the faster speeds for smaller and softer metals. Aluminium and brass like to be machined at faster speeds and show a nicer surface finish because of this. Also really small steel items will cut more freely at the proper speeds and again provide a nicer surface finish.

There's information around on the web as charts for "cutting speeds for different metals". The rates are given in SFM or Surface Feet per Minute. Now that's for a flat tool passing over a surface. To translate that to RPM you can also find charts that convert the SFM to RPM vs diameter. It all seems complicated but if you stop and think about it the light will come on :)

The SFM charts are typically maximum values given for reasonable life from tooling vs speed of production. So if there's a single value don't be afraid to work at down around 70% of the number. Or in some cases as low as half the rate given. But much less and the metal won't really come off cleanly as it could. So some experimenting might be needed. If you run at or near the maximum expect some machines to be strained and begin doing things like chattering. Also the edge on your tooling will dull sooner. All of this is why I typically work at some lower value that still gives me a nice finish.

If you You Tube for "turnwright machine works" and watch Kieth Fenner doing his machining the tool speeds seem slow to the point of laziness. But his tooling likely stays sharper for FAR longer as a result.

And what Trev mentioned about the morse taper is valid. A 1.25" opening on the nose of the spindle does suggest a roughly 1 inch bore at the rear of the spindle.

Assuming an MT3 spindle you may want to look at an MT3 to ER collet chuck to use in your lathe as an addition to the regular 3 and 4 jaw chucks. The collet setup is nice for many things due to the far better and more consistent centering. And by using an MT3 to ER chuck setup it moves the work out far enough that you are not crowding the head with the carriage.
 
Toolposts either the aloris-style wedge type or the 40-postion Swiss multifix style. Both available in Chinese versions, the aloris being the more common and cheaper

+1 for the ER32 collet setup. Very cheap and fantastic for small parts
 
Just got done working.... Started at 6:30 am and just finshed @ 9:00 pm tonight ... Long days , looking forward to getting home. And doing a little more learning. There a guy near Ottawa that sell all kind of lathe/ milling/ everything lol parts. I think I might go and see him this week end. I didn't get a lot of tooling when I bought the lathe. It did come with a Bronson ... Think that's what it call 4 jaw chuck , but that's it. Will be on the look out for a face plate and dog. Follow rest .... And any small parts.
Brian
 
Loving that heavy-10. Wish I had held out for one over my 9A, but none were to be had at the time. Don;t listen to the nay-sayers, that machine will serve you very well for anything you could need to do on a gun provided the longer barrels you work on are smaller than the spindle bore. Gunsmithing is not a game of hundred-thousandths of runout. And really, on a worn heavy-10, runout from bed wear is likely the only real concern.

Here's my 9A - love it.

DSCN0860.jpg
 
Nice looking #9 , would love to have the threading dial you have in the pic ,will one off one of the new South Bends work?
Picked up a new live center, and new tool post, also pickup some parts for a small mill...things are looking up!
Looking at making a spider for the other end of the head, and still looking for a steady rest....might have to build one.
Cheers
Brian
 
BCRider said:
If you have someone that can weld for you making a steady rest would not be that big a deal.
Click to expand...

Yep I have welded for a lot of years, I learn backwards.... Started on tig, then mig.... And the. Stick lol
I have lots of little project, I'd like to get done �� ..... Someday
 
BCRider said:
Just looking back at that picture of the spindle nose and the roughly 1.25" opening. That's a #4 morse taper spindle you've got there. At some point you may want to look into picking up one of these and some ER32 collets as one of your more accurate and easy to use work holding options.

http://www.ebay.com/itm/New-List-Sa...300061?hash=item3f5ba2421d:g:PFAAAOSwAodWFH01
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There is a special adapter sleeve to fit the spindle taper to reduce to #2 or #3 morse taper. I have both and purchased them on ebay.
I've heard of people making one from a MT5 adapter, reducing the length because it is way too long. My South Bend sleeves are only about 2" long, maybe a little more.
 
Claven2 said:
Loving that heavy-10. Wish I had held out for one over my 9A, but none were to be had at the time. Don;t listen to the nay-sayers, that machine will serve you very well for anything you could need to do on a gun provided the longer barrels you work on are smaller than the spindle bore. Gunsmithing is not a game of hundred-thousandths of runout. And really, on a worn heavy-10, runout from bed wear is likely the only real concern.

Here's my 9A - love it.

DSCN0860.jpg
Click to expand...


I have that lathe's twin, in worse cosmetic condition. :p
 
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